Vocal cords, also known as vocal folds, are two bands of muscle tissue located in the larynx, or voice box. They vibrate when air from the lungs passes through them, producing sound. The pitch of the sound can change based on the tension and length of the vocal cords, which can be adjusted by the surrounding muscles. These structures play a crucial role in speech and singing. When we speak or sing, the brain sends signals to the muscles around the vocal cords, allowing them to open and close rapidly. This process is essential for creating different tones and volumes in our voice.